Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932501AbWB1Vec (ORCPT ); Tue, 28 Feb 2006 16:34:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932584AbWB1Vec (ORCPT ); Tue, 28 Feb 2006 16:34:32 -0500 Received: from isilmar.linta.de ([213.239.214.66]:15853 "EHLO linta.de") by vger.kernel.org with ESMTP id S932501AbWB1Vea (ORCPT ); Tue, 28 Feb 2006 16:34:30 -0500 Date: Tue, 28 Feb 2006 22:34:28 +0100 From: Dominik Brodowski To: Matt Mackall Cc: Dave Jones , Adrian Bunk , Dmitry Torokhov , davej@codemonkey.org.uk, Zwane Mwaikambo , Samuel Masham , Jan Engelhardt , linux-kernel@vger.kernel.org, Andrew Morton , cpufreq@lists.linux.org.uk, ak@suse.de Subject: Re: Status of X86_P4_CLOCKMOD? Message-ID: <20060228213428.GA31044@isilmar.linta.de> Mail-Followup-To: Matt Mackall , Dave Jones , Adrian Bunk , Dmitry Torokhov , davej@codemonkey.org.uk, Zwane Mwaikambo , Samuel Masham , Jan Engelhardt , linux-kernel@vger.kernel.org, Andrew Morton , cpufreq@lists.linux.org.uk, ak@suse.de References: <20060222024438.GI20204@MAIL.13thfloor.at> <20060222031001.GC4661@stusta.de> <200602212220.05642.dtor_core@ameritech.net> <20060223195937.GA5087@stusta.de> <20060223204110.GE6213@redhat.com> <20060228194628.GP4650@waste.org> <20060228200916.GA326@redhat.com> <20060228204720.GD13116@waste.org> <20060228205758.GA16268@isilmar.linta.de> <20060228212632.GE13116@waste.org> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20060228212632.GE13116@waste.org> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1443 Lines: 34 On Tue, Feb 28, 2006 at 03:26:32PM -0600, Matt Mackall wrote: > > So even if the battery lasts longer, you don't have anything of it, 'cause > > the CPU can even compute _less_ in this longer time-span. Remember that > > idling doesn't count... > > Which is different from other power-saving modes how? If it means I > can read my email longer on the plane, it's a power-saving mode. But you can't... [*] > > > In short, power usage and heat production are _the same thing_. > > > > Yes and no. The heat production is more levelled if you use throttling, so > > the temperature achieved is lesser, which might cause fans not having to > > start or air conditioning having less work to do. > > The time scale for heat propagation is enough slower than throttling > that I'd expect this difference to amount to approximately nil. For short-term load spikes, yes. If your server has a task which takes up one hour at full time, and the temp reaches 45? C then, but you have nothing else for it to do overnight, then it does might sense to throttle it to 50%, which will mean two hours, but only 40? C. Dominik [*] unless the idling algorithm is broken and does not enter C2-type idle states. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/